Rendering issue. Jumping text to the top of the page. Overlapping text.




3 years ago
3 years ago


(Reporter: mnmnc, Unassigned, NeedInfo)


34 Branch
Windows 8.1

Firefox Tracking Flags

(Not tracked)



(1 attachment)



3 years ago
Created attachment 8531311 [details]
RenderingEngineFailure.jpg - shows the problem with overlapped layers and sequential numbers being displayed out of the blue

User Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:34.0) Gecko/20100101 Firefox/34.0
Build ID: 20141125180439

Steps to reproduce:

Opened a webpage (, moved to repository, clicked to edit the file.

Firefox 34. Windows 8.1.
Hardware acceleration for Flash - disabled.

Actual results:

While editing and moving the cursor around the page and performing normal editing actions, some of the file began to render on top of the page like a second layer on top of the normally rendered page. The incorrectly rendered text flickers when you move the cursor over some animated element on page - to be exact I moved the cursor over the scrollbar (the github scrollbar not Firefox scrollbar) on page, but I'm not sure if that was what triggered the issue.
This is not the first time that happens and I think it might have happened on other pages as well. I'm pretty sure that if this is an actuall bug it affected late releases of Firefox 33 as well.
Please take a look at the attachment. You can clearly see the rendering failure. What is really interresting is that the numbers that show up in a ordered sequence (171819202122232425) over and over in the picture attached, are not part of the text I was editing. It might me some memory leak, it might be some javascript issue on the github page side. I left that for you to decide. Let me know if more information will be required - i will provide it gladly.

Expected results:

The page should be rendered correctly.

Comment 1

3 years ago
Can you post the graphics information from about:support?

And can you try if you can reproduce this problem in safe mode? ( )
Flags: needinfo?(hyp3rcain)

Comment 2

3 years ago
Sure. Here are the details you requested:

Data sterownika	9-15-2014
GPU #2 Active	false
ID dostawcy	0x1002
ID subsystemu	30111043
ID urządzenia	0x6819
Okna ze sprzętowym przyspieszeniem grafiki	1/1 Direct3D 11 (OMTC)
Opis adaptera	ASUS R7 265 Series
RAM adaptera	2048
Renderer WebGL	Google Inc. -- ANGLE (ASUS R7 265 Series Direct3D9Ex vs_3_0 ps_3_0)
Sterowniki adaptera	aticfx64 aticfx64 aticfx64 aticfx32 aticfx32 aticfx32 atiumd64 atidxx64 atidxx64 atiumdag atidxx32 atidxx32 atiumdva atiumd6a atitmm64
Wersja sterownika	14.301.1001.0
windowLayerManagerRemote	true
Włączone Direct2D	true
Włączone DirectWrite	true (6.3.9600.17415)
AzureCanvasBackend	direct2d
AzureContentBackend	direct2d
AzureFallbackCanvasBackend	cairo
AzureSkiaAccelerated	0

I'll try to reproduce in safe mode. I had never experienced this before. I always did use Adblock Plus, Ghostery and DownloadHelper. For a few months now I am also using addon called PrivacyBadger. I never had any problems with the former ones, hence I suspect that if this is an issue caused by addon - it will be PrivacyBadger fault.


3 years ago
Component: Untriaged → Graphics
Product: Firefox → Core
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